Devices using various types of media such as optical discs, magnetic optical discs, and flexible magnetic disk are known in the art of data storage devices. Among them, hard disk drives (hereinafter referred to as HDDs) have become popular as storage devices for computers to such an extent that they are one of the storage devices indispensable for today's computer systems. Further, not limited to the computers as described above, HDDs are becoming more and more widely used in various applications. For example, HDDs are used for video recording/reproducing devices, car navigation systems, cellular phones, and as removable memories for use in digital cameras.
A HDD includes a magnetic disk, a head slider, and an actuator. Data is stored on the magnetic disk. The head slider reads data from, and/or writes data to, the magnetic disk. The actuator moves the head slider to a desired position over the magnetic disk. The actuator is driven by a voice coil motor, pivotally moving about a pivot. As a result, the actuator moves the head slider radially above a spinning magnetic disk.
The head slider moves to a desired track formed on the magnetic disk, reading or writing data. The head slider includes a slider, on which a head element portion is disposed. The head element portion includes a write element and/or a read element. The write element converts an electric signal to a corresponding magnetic field according to the data to be recorded onto the magnetic disk. The read element, on the other hand, converts a magnetic field from the magnetic disk to a corresponding electric signal.
The actuator includes an elastic suspension. The head slider is fixed to the suspension. The head slider can fly at a predetermined gap above the magnetic disk by the following action. Specifically, pressure generated by viscosity of air between an ABS (air bearing surface) of the slider opposing the magnetic disk and the spinning magnetic disk balances pressure applied in the direction of the magnetic disk by the suspension. The suspension includes a gimbal and a load beam. The gimbal holds the head on the side of a surface opposing the magnetic disk. The load beam holds the gimbal on the side of the surface opposing the magnetic disk. The gimbal is formed to be deformable such that the slider can incline in a predetermined direction to offset runout of the magnetic disk.
The actuator also includes a wire structural portion for transmitting head signals. In this specification, the wire structural portion is called a “trace.” The trace transmits signals between a preamp IC disposed near the pivot of the actuator and the head slider. The trace has a proximal end connected to the head slider. The preamp IC is mounted on an FPC, to which a distal end of the trace is connected through soldering or other method.
A trace, not fixed to the actuator, can oscillate, thus affecting head positioning. For example, Japanese Laid-Open Patent No. 2004-355721 (“Patent Document 1”), discloses an arrangement, in which the trace is accommodated in a slit surrounded by two protruding walls, thereby suppressing vibration of the slider caused by an air flow generated through spinning of the disk. The arrangement includes a wire support member mounted with an adhesive to an outer side surface of an actuator arm. The wire support member includes a slit that extends in a longitudinal direction, in which the trace is accommodated.
Use of the member for accommodating the trace as described above helps suppress fluttering phenomenon of the trace caused by the air flow generated from spinning of the magnetic disk. It is to be noted herein that, when the trace accommodating member is to be fixed to the outer side surface of the actuator arm using the adhesive, it is necessary that the adhesive be hardened in a condition, in which the trace accommodating member is positioned on the surface after the adhesive has been applied.
The wire support member should preferably be formed of a resin from the standpoints of prevention of damage to the trace and ease of manufacture of the wire support member. A resin molded wire support member is, however, easily deformed in the pivot direction. It is therefore particularly important to fix the wire trace member temporarily before hardening. To position the wire support member in the pivotal movement direction, the wire support member may, for example, be arranged to include a structure that clamps an upper and lower surface of the actuator arm. The wire support member is thereby positioned in the pivot direction.
Such a structure, however, contributes to an increased dimension (thickness) in a vertical direction (pivot direction) of the actuator. Design of the HDD calls for mounting of various components in an enclosure having predetermined dimensions. This requires that the actuator arm be made to be thin enough to accommodate a greater number of magnetic disks, in particular. This is particularly conspicuous in HDDs of 2.5 inches or less having a thin enclosure.